Method of and apparatus for fabricating wood structures

ABSTRACT

A method and apparatus for fabricating wood structures utilizing a C-shaped press having an upper platen and a lower platen which are relatively movable toward and away from one another for driving nailing plates into two or more wood members from above and below, in which the wood members are held in position for being nailed together on a plurality of stands arranged on lines bounding the structure. Each such stand includes means for supporting the wood members and has a holder plate adapted to hold a nailing plate for being driven upwardly into the wood member from below by the lower platen of the press. The supporting means and the holder plate are so mounted on the stands as to enable lateral entry of the lower platen of the press from either side of the stand to an operating position below the holder plate. The press is mounted for generally lateral movement with respect to the press substantially sidewise into and away from an operating position at each such stand. Means are provided for preventing operation of the press unless it is in an operating position at a stand.

United StatesjPatent n91- Moehlenpah v v [111 3,824,919 51 July 23,1974

[ METHOD OF AND APPARATUSFOR FABRICATING WOOD STRUCTURES [76] Inventor:Walter G. Moehlenpah, 9906 Old Warson Rd., Ladue, Mo. 63124 [22] Filed:Nov. 10, 1972 [21] Appl. No.: 305,518

[52] US. Cl 100/35, lOO/DlG. l3, 100/53,

7 100/231, 100/269 R, 227/152 [51] Int. Cl B30b 13/00 [58] .Field ofSearch 100/35, 53, 231, 269 R,

l00/DIG. 13; 227/152; 335/205 [56] References Cited UNITED STATESPATENTS 3,068,484 12/1962 Moehlenpah et al. l00/DlG. 13 3,069,68412/1962 Moehlenpah et al. 100/DlGhl3 3,487,430 12/1969 Schmitt loo/DIG.13

Primary Examiner-Billy J. Wilhite Attorney, Agent, or Firm-Koenig,Senniger, Powers and Leavitt [57] ABSTRACT A method and apparatus forfabricating wood structures utilizing a C-shaped press having an upperplaten and a lower platen which are relatively movable toward and awayfrom one another for driving nailing plates into two or more woodmembers from above and below, in which the wood members are held inposition for being nailed together on a plurality of stands arranged onlines bounding the structure. Each such stand includes means forsupporting the wood members and has a holder plate adapted to hold anailing plate for being driven upwardly into the wood member from belowby the lower platen of the press. The supporting means and the holderplate are so mounted on the stands as to enable lateral entry of thelower platen of the press from either side of the stand to an operatingposition below the holder plate. The

. press is mounted for generally lateral movement with respect to thepress substantially sidewise into and away from an operating position ateach such stand. Means are provided for preventing operation of thepress unless it is in an operating position at a stand.

29 Claims, 11 Drawing Figures PAIENTEDJULZBIQH SHEEY 2 BF 6 innnnnnnnPATENIEDJULZIHQH sum 3 or 6 FIG.5

FIG.6

PATENTED HLN 3.824.919

SHEET 6 OF 5 PEG-.IO

, 1 METHOD OF AND APPARATUS FOR FABRICATING WOOD STRUCTURES BACKGROUNDOF THE INVENTION This invention relates to the fabrication of woodstructures, and more particularly to a method of and apparatus forfabricating wood structures utilizing a C- shaped press to drive nailingplates into two or more wood members.

U.S. Pat. Nos. 3,068,484 and 3,069,684 show prior art truss fabricatingapparatus utilizing a C-shaped press having an upper platen and a lowerplaten for driving nailing plates into two or more wood members fromabove and below having a plurality of pedestals (or stands) forsupporting the wood members in position. Each of the pedestals includesa holder or locator 2 upward or downward force thereto. The press isthen opened and moved generally laterally with respect to the presssubstantially sidewise out of the stand and over to the next successivestand. The press is maintained adjacent to the wood members supported bythese stands as it is moved and it enters the next successive standsubstantially from the side thereof to bring it to its operatingposition at the next successive stand. The press is again operated todrive the nailing plates into the wood members, and the latter two stepsare repeated as the press is moved between successive stands thereby tonail additional wood joints.

Apparatus of this invention generally comprises a series of stands forholding the wood members which are plate for holding a lower nailingplate in position below the wood members for being driven upwardly bythe lower platen of the press which is adapted to be positioned in anailing plate driving position within the pedestal. Other prior artfabricating apparatus is shown in U.S. Pat. No. 3,487,430. Wood membershave also been supported in a cantilevered position forforming jointswith nailing plates. However, in all such prior known wood fabricationsystems the press was not moved laterally (with respect to the press)substantially sidewise out of one stand and over to the next stand forsidewise entry thereinto where the press would operate to drive nailingplates into the wood members without applying any substantial net upwardor downward force, and the presswas not prevented from operating if thepress was in other than an operating position at one of the stands.

SUMMARY OF THE INVENTION Among the several objects of this invention maybe noted the provision of methods of and apparatus for fabricating woodstructures which minimize the time and effort required in forming anumber of joints between wood members such as neededin fabricating roofand floor trusses or the like; the provision of such to be securedtogether at their joints by nailing plates to form a wood structure. Thestands are arranged at joints, and each such stand has a support andmeans cantilevered relative to the support for holding wood members withclearance therebelow. A press is provided having an upper platen and alower platen which are relatively movable toward and away from oneanother for driving nailing plates into thewood members from above andbelow. Also provided is means mounting the press for generally lateralmovement of the press substantially sidewise into and away from anoperating position at each of the stands for driving nailing apparatusin which nailing plates are driven into the wood members withoutapplying any substantial net upward or downward .force thereto wherebylight, strong joints are formed between the wood members; the provisionof such apparatus which utilizes a single press movable fromstand-to-stand substantially along a line of stands to form said jointsand which facilitates positioning of the press in an operating positionat each of the stands; and the provision of such methods and apparatuswhich permit more rapid and efficient production of such relativelylarge wood structures.

In general, the method of this invention utilizes a C- shaped presshaving an upper platen and a lower platen which are relatively movabletoward and away from one another for driving nailing plates into two ormore wood members from above and below, and comprises supporting thewood members, which are to be nailed together at joints to form a woodstructure, on a plural ity of stands arranged at the joints, withclearance below the wood members for movement of the lower platen of thepress underneath the wood members. The press is brought into anoperating position at one of the stands with its lower platen below thewood members. The press is then operated to drive the nailing plate intothe wood members without applying any substantial net plates into thewood members held by that stand. Preferably means are provided forpreventing operation of the press unless it is at an operating positionat one of said stands.

Other objects and features will be in part apparent and in part pointedout hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view showingapparatus of this invention set up to fabricate a W-type truss;

FIG. 2 is a front elevation of the apparatus, showing a hydraulic pressassembly;

FIG. 3 is an enlarged plan view of a first embodiment of one of thestands with parts broken away;

FIG. 4 is a front elevation of the stand of FIG. 3 with the lowerportion of the hydraulic press (shown in phantom) in its operatingposition;

FIG. 5 is an enlarged plan view of a second embodiment of one of thestands with parts broken away;

FIG. 6 is a front elevation of the stand of FIG. 5 with parts brokenaway;

FIG. 7 is a side elevation of the stand of FIG. 5 showing the press inits operating position, with respect to the stand, and showing means forfacilitating positioning of the press in its operating position;

FIG. 8 is a hydraulic schematic;

FIG. 9 is anelectrical schematic;

FIG. 10 is a semi-diagrammatic view depicting movement of the press(shown in phantom) into and out of its operating position at a Stand ofthis invention; and

FIG. 1 l is a semi-diagrammatic view depicting movement as in the priorart of a press into and out of its operating position at a prior artstand.

Corresponding reference characters indicate corresponding partsthroughout the several views of the drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings,FIGS. 1 and 2 show apparatus of this invention, generally indicated at1, for fabricating wood structures, e.g., wood trusses, such asindicated'at T. The apparatus comprises a series of stands generallyindicated at 3 for holding precut wood members M which are to be securedtogether'at their joints by upper and lower nailing plates UN and LN,respectively. The stands are arranged at the joints on straight linesbounding the wood structure to be fabricated and each stand has asupport or base generally indicated at 5 and means indicated at 7 forholding the wood members cantilevered relative to the support. Theapparatus further comprises a C-shaped hydraulic press generallyindicated at 9 which has an upper platen 1 1 and a lower platen 13 whichare relatively movable toward and away from one another for drivingnailing plates into the wood members from above and below. Meansgenerally indicated at 15 carries the press 9 for moving it into anoperating position (the position of the lower platen is indicated at Ain FIG. for driving the nailing plates into the wood members M at one ofthe stands, for movement in a generally lateral direction with respectto the press(as shown by the arrows in FIG. 10) substantially sidewiseout of its operating position at the one said stand and over the nextsuccessive stand and into its operating position at this next successivestand, with the press being maintained substantially adjacent woodmembers M supported by these stands as it is moved. Means also carriesthe press in such manner so as to drive the nailing plates into the woodmembers from above and below without exerting any substantial net upwardor downward force (aswill be hereinafter described) on the wood membersby the platens.

As shown in FIG. 1, the apparatus 1 is set up to fabricate a W-truss,but it will be understood that the method and apparatus of thisinvention may be adapted to fabricate a wide variety of triangular orflat trusses. More particularly, the apparatus is shown as comprising apluralityofthe stands 3 movable to different posi- 4 toward the interiorof truss T, and extends up above the top 37. The hollow wall 39' isformed by an outer vertical wall 41 secured as by welding to the upperportions of the side channels 33. This outer vertical wall carriesinwardly facing flanges 43 at each side and has an inner vertical wall45 secured thereto.

Referring now to FIG. 7, the wood member holding means 7 includes twocantilever arms, each designated 47, in side-by-side spaced relation andextending forwardly over the base top 37 from the outer sides of hollowwall 39. The top surfaces of the cantilever arms 47 are positioned abovethe top of wall 39 and are adapted to support the wood members M inposition to be secured together by upper nailing plates UN and lowernailing plates LN. The cantilever arms are located above the base top'37a sufficient distance to permit the entry of the lower platen 13 of thepress 9 from one lateral side or the other of the stand belowthecantilever arms 47 to its operating position (as shown in FIGS. 4, 7 and10) in a vertical plane generally midway between the cantilever arms.The top surfaces of the cantilever arms are spaced from the top surfaceof the tions to correspond to the joints at the intersections of two ormore wood members M in their assembled position. The lower chord stands,indicated at 17, and the peak stand '19, are mounted on a lower chordtrack 21 and a center track 23, respectively. The upper chord stands25are slidably mounted on the floor and are adapted (when moved to theirdesired positions) to be rigidly clamped at those positions by lockingextensible telescoping links 27 and 29. The track mounted stands eachhave a screw clamp 31 for rigidly clamping them in their desiredpositions on their respective tracks. The stands 17, 19 and 25 generallycorrespond to the pedestals 9, 13, 17, 19 and 21 shown in U.S. Pat. No.3,068,484, tracks 21 and 23 herein correspond to tracks 11 and 15, andtelescoping links 27 and 29 correspond to links 23 and 25, respectively,in the abovementioned patent. It will be understood that the stands 3 ofthis invention may be mounted on the track arrangement shown in U.S.Pat. No. 3,693,542 in which event no telescoping links are used.

As shown in FIGS. 3-7, each stand 3 includes a support or base 5comprising a pair of inwardly facing channels, each designated 33, whichconstitute stand side members. The channels 33 are joined at theirbottoms by angle members 35 and have a horizontal top 37 extendingbetween theupper portions of the channels constituting the top of thebase. A vertical hollow wall 39 is secured to the back of the base,i.e., the side lower platen 13 a distance sufficient to accommodate thelower nailing plate LN arranged with its teeth pointing up for beingdriven into the wood members from below. As shown in FIG. 4, thecantilever arms 47 are laterally spaced from one another a distancegreater than the width of the lower platen 13 of the press for entry ofthe lower platen between the arms when the press is in its operatingposition and the lower platen is moved upwardly to drive the lowernailing plate LN into the wood members.

At the back ends of the cantileverd arms 47, a horizontal member 49 issecured to the upper portion of outer wall 41 with the top surface ofmember 49 at substantially the same level as the top surface of thecantilever arms. Each arm 47 is cantilever-supported by an angle member51 secured to the outer wall 41 and extending outwardly therefrom, andmember 49 is supported by an angle member 53 welded to the upper portionof the outer wall. The cantilever arms 47 and the horizontal member 49correspond to the channelshaped guides 103 and 71, respectively, shownin the aforementioned U.S. Pat. No. 3,068,484, and are adapted to carryclamping and aligning means (not shown) similar to those indicated byreference numberals 75, 77 and 105 in the last-said patentfor holdingthe wood members M.

Wood member holding means 7 further includes a holder or a locator plate55 cantilevered outwardly from the support 5 constituting means at eachstand for holding a lowernailing plate LN below the wood members Msupported on the cantilever arms 47. The holder or locator plate 55 ispositioned between the cantilever arms 47 and is carried by the supportfor upward and downward movement relative thereto for being drivenupwardly by the lower platen 13 of the press 9 from a lower retractedposition (as shown in FIG. 4) below the top surface of the cantileverarms 47 to drive the lower nailing plate LN positioned thereon into thewood members from below. The operating position (e.g., A in FIG. 10) ofthe press is more particularly defined as that position at each of thestands in which the press and its platens are substantially centeredbetween the cantilever arms 47 and the platens are positioned verticallyrelative to the wood members M and fore and aft relative to wall 45 soas to be above and below the joint in the wood members with lower platen13 below holder plate 55 when the latter is in its lowered retractedposition and with the upper platen 11 above the joint in the woodmembers. Thus, with the press in its operating position, the press maybe operated to drive the nailing plates into the wood members withoutdamage to the stand. The operating position of i the press is also shownin FIGS. 4 and 7.

Locator plate 55 is cantilever-supported outwardly from the wall 45 by apair of rods, each designated 57, secured to its lower face adjacent theback edge thereof. Means generally indicated at 58 is carried by thestand for guiding rods 57. More particularly, in one embodiment, asshown in FIGS. 3 and 4, this guide 1 guide rollers 64a, 64b of nylon orthe like and which are vertically movable within hollow wall 39 suchthat the guide rollers and the hollow walltogether constitute guidemeans 58. In both of the abovedescribed embodiments, the upper edge ofwall 45 constitutes a stop and prevents the locator plate from movingsubstantially below its lowered retracted position, and the locatorplate is gravity-biased to remain in its lowered retracted position.Additionally, the guide means 58 of both of the above-describedembodiments accurately maintains the holder plate in a substantiallyhorizontal position as the holder plate is moved from its lowerretracted position to drive the lower nailing plate LN positionedthereon into the wood members M from below. Thus, the teeth of the lowernailing plate are maintained in substantially perpendicular relation tothe lower surface of the wood members M so that they engage the lowersurface of the wood members at substantially the same time thereby tofacilitate forming tight, strong joints. Locator strips 65 areoptionally provided on the top surface of the locator plate toaccurately position the lowernailing plate LN relative to the respectivewood members supported thereabove.

Referring now to FIG. 2, the hydraulic press 9 may correspond to thepress indicated at 35 in US. Pat. No. 3,068,484, and it is herein-shownto be supported for universal movement by mounting means which comprisesa yoke 66, a cable 67 attached to the yoke and to one end of a boom 69.The latter is counterbalanced by a hydraulic pump and electric motorassembly 71 at the other end of the boom. A pivotal hanger 73 suspendsthe boom from a carriage 75 which is movable along an overhead l-beam 77suspended from the ceiling, or from other overhead structure. The hanger73, the counterbalanced boom 69, and the movable carriage 75 permithorizontal movement of the press from stand to stand for nailing platedriving purposes and permit vertical movement during driving of thenailing plates into the wood members without exerting any substantialnet upward or downward force on the wood members. A substantial netupward or downward force on the wood members is one which would move thewood members relative to each other to open the joints therebetween, orwould force a wood member out of its clamps, or would deflect thecantilever arms 47. Such a substantial force may be applied to the woodmembers by one platen of the press exerting a greater force on thewoodmembers than the other, or by supporting all or a significant part ofthe weight of the press on the wood members. Generally, such asubstantial net upward or downward net force is one that does not exceedabout 5 percent of the capacity of the press and preferably does notexceed about 500 lb. It will be understood that press 9 may also becarried by a movable gantry, and in instances where a significant upwardor downward force on the wood members is not critical, the press may bemounted for movement in a horizontal plane but without being free tomove vertically.

As shown in FIG. 7, the press 9 comprises a C-shaped frame 79 on whichthe lower platen 13 is fixed and carries the upper platen 11 which ismovable via a hydraulic power cylinder 81. The hydraulic cylinder isinterconnected to the hydraulic pump of assembly 71 by hydraulic fluidslines 83 and 84 (FIG. 8) for providing hydraulic fluid under pressure tomove the upper platen toward and away from the lower platen. Pistol griphandles 85 are provided on opposite sides of frame 81 (only theleft-hand handle 85 is shown in FIG. 7) so as to enable the pressoperator readily to control the movement and operation of the press.Push button electrical switch PB1 is mounted on one of the handles 85and switch PB2 is positioned on the other for controlling movement ofthe carriage along I-beam 77. Push button electrical switches PB3 andPB4 are also respectively provided on handles for controlling operationof the platens of the press. Hydraulic and electrical circuits (FIGS. 8and 9) including the abovementioned push button switches will be morefully explained hereinafter.

In accordance with this invention, means generally indicated at 87 (seeFIG. 7) is provided for preventing operation of theplatens of press 9 todrive nailing plates into the wood members except when the press is inits operating position (see FIGS. 4 and 7) thus insuring that the presswill not damage the stand by being operated when it is improperlypositioned relatively to the holder and the stand, and further insuringthat nailing plates LN and UN will be properly driven into the woodmembers from above and below to form a tight, strong joint. Moreover, bypreventing operation of the press, means 87 facilitates positioning ofthe press in its operating position at each of the stands 5.

More particularly, means 87 includes a magnetic switch 89 (e.g., amagnetic reed switch such as manufactured by Cutler-Hammer) and a magnet91 (a permanent magnet) together constituting proximity sensing meansresponsive to movement of press 9 into its operating position at each ofthe stands 5. Magnetic switch 89 is mounted on the nose of press frame79 below lower platen 13 and is actuable in response to a magnetic fieldof a predetermined strength. The magnetic switch is connected in serieswith push buttons PB3 and PB4 to prevent operation of the press unlessthe magnetic switch is also actuated. Magnet 91 is mounted on inner wall45 of the stand in the vertical central plane between arms 47 (see FIGS.4 and 5) so that it is adjacent the magnetic switch when the press is inits operating position. Magnet 91 produces a magnetic field ofsufficient strength (i.e., the effective field of the magnet) to actuatethe switch when the switch 7 is within the effective field. Typically,this effective field extends from the magnet about 1% inches in alldirections. Thus, unless the press is properly positioned at a stand inits operating position with its switch 89 in the effective field ofmagnet 91, operation of the 'press is prevented. It will be understoodthat means 87 may be constituted by components other than a magnet andmagnetic switch. For example, photoelectric'or induction-type proximityswitches carried by the press may also be used to signal when the pressis in its operating position.

The hydraulic pump and electric motor assembly 71 heretofore describedincludes a conventional hydraulic pump 93 mounted in a tank or sump 95on the right end of hanger beam 69 (as viewed in FIG. 2). An electricmotor 97 is mounted on the sump for driving the pump. The motor issupplied with current from an electrical source(not shown) via line 99.Carriage 75 is driven along I-beam77 by a hydraulic carriage motor 101supplied with hydraulic fluid under pressure frompump 93 via lines 103and 105, this arrangement being similar to the carriage drive shownin'FIGS. 13-15 of the'previously mentioned US. Pat. No. 3,068,484.

F IG'. 8 shows the hydraulic circuit for press 9 and carriage motor 101.Pump 93 is supplied with hydraulic fluid from sump 95 via a line 107.The pump via a line 109 directs hydraulic fluid under pressure to aninlet port Vla of a three-way valve V1. The spool of valve motor vialine 105. Valves V7 and V8 together constitute means for regulating thespeed of motor 101. Check valves V9 and V10 are included in lines 103and 105, respectively, and are connected in parallel to their respectivemetering valves V7 and V8 to permit low pressure fluid from the motor todrain to the sump without passing through the metering valves. Thesecheck valves each block the flow of pressurized fluid to the motor andthus force the liquid through their respective metering valve.

Referring now to FIG. 9 illustrating the electrical circuit, pump motor97 is supplied with power from an electric power source via line 99including lines L1, L2 and L3. The primary of a step-down transformer113 is connected across lines L2 and L3 by lines 115 and 117. Thesecondary of the transformer supplies electrical power to lines 119 and121. Switch P131 is connected across lines 119 and 121 in a line 123including solenoid Z. Switch PB2 is connected across lines 119 and 121in a line 125 including solenoid Y. Push buttons PB3 and PB4 andmagnetic switch 89 are connected in series across lines 119 and 121 in aline 127 including a time delay relay TD1 which prevents operation ofcarriage motor 101 while the press is hydraulically actuated. This timedelay relay includes contacts C1, C2, C3 and C4 with contact C1 includedin a line 129, contacts C2 and C3 included in a line 131, and

. contact C4 included in line 121. Upon energization of V1 is controlledby solenoids Wand X.- This valve has I a pressure outlet'port Vlbconnected to the upper end of hydraulic cylinder 81 via line 83 .forsupplying hydraulic fluid-under pressure to the press for effectingmovement of the platens toward one another, a second outlet port Vlc.connected to the lower end of the hydraulic cylinder via line 84 forsupplying hydraulic fluid to the lower end of the hydraulic cylinder toeffect movement of the platens away from one another after the joint inthe woodmembers has been formed, and a third outlet port Vld connectedto the inlet port V2a of a valve V2.via a line 111 for supplyinghydraulic fluid to motor 101.

Pressure relief valves V3 and V4 are provided in line 109 to returnhydraulic fluid to sump 95 in the event pressure in the hydraulic systemexceeds a predetermined .value. More particularly, valve V3 isadjustable to control the pressure supplied to the press to thus varythe maximum force the platens may exert on the wood members, and valveV4 is a safety valve preset to limit the maximum pressure in. thesystem. An unloader valve V5 is included in line 83 operable in responseto increase in pressure in line 84 to drain fluid from the hydrauliccylinder to the sump as the platens are moved apart from one another. Arelief valve V6 is provided in line 84 to relieve pressure therein andthus limit the force applied to the hydraulic cylinder when the upperplaten is fully retracted and to limit the pressure of the fluidsupplied to motor 101.

Valve V2 is a three-way valve whose spool is controlled by solenoids Yand Z. In addition tov port V2a, valve V2 has an outlet port V2bconnected to one side of carriage motor 101 via line 103, a secondoutlet port V2c connected to the other side of the motor by line 105,and a drain port V2d in communication with sump 95. Line 103 includes anadjustablemetering valve V7 for controlling the flow of hydraulic fluidto motor 101 via line 103, and a similar metering valve V8 is includedin line 105 to control the flow of fluid to the relay TDl (which canonly occur when the press is in its operating position at a stand Sandmagnetic switch 89' is actuated and when both push buttons PB3 and PB4are depressed), contacts Cl and C2 close, and contacts C3 and'C4 open.The closing of contact C1 energizes solenoid W and the opening ofcontact C4 prevents energization of solenoids Y and Z and thus preventsmovement of carriage along beam 77. Energization of solenoid W shiftsthespool of valve V1 from the position shown in FIG. 8 so that hydraulicfluid is supplied to the press via line 83 to effect movement of theplatens toward one another for driving the nailing plates into the woodmembers. Releasing either of the push buttons PB3 or PB4, or moving thepress from its operating position and thus opening magnetic switch 89,de-energizes relay TDl. This in turn instantly opens contact C1 andcloses contact C3 thereby to respectively de-energize the solenoid Wand'to energize solenoid X. This shifts the spool in valve V1 back tothe position shown in FIG. 8 and permits hydraulic fluid to flow inlines 84 for niovingthe platens apart and in line 111 for supplyinghydraulic fluid to valve V2. After a time delay to permit sufficientseparation of the platens, contacts C2 of the delay relay open andcontacts C4 close thereby to respectively de-energize solnenoid X and tocomplete line 121 so that upon actuation of push buttons FBI and PB2,motor 101 will operate to drive the carriage along I-beam 77 to move thepress from stand to stand.

In operation, the stands 3 are arranged to correspond to the joints ofthe wood members M which are to be nailed together by nailing plates UNand LN to form the desired wood structure T. The lower nailing plates LNwith their teeth pointing up are then placed on the holder or locatorplates 55 of the several stands in proper position as determined bylocator strips 65. The precut wood members M are then placed in positionand supported on the cantilever arms 47 and clamped in position to besecured together by the above said clamping and aligning means. Theupper nailing plates UN with their teeth pointing down are then manuallyplaced over the joints of the various wood members as shown in FIG. 4.It will be noted that operation of the press is prevented by magneticswitch 89 unless the press is in its operating position at one of thestands, thereby facilitating rapid and efficient positioning the pressin its working station.

In accordance with the method of this invention (as particularlyillustrated in FIG. the hydraulic press 9 is moved to one of the stands3, e.g., the stand at the end of one of the straight lines of standsthat bound the wood structure T, and the lower platen 13 of the press ismoved sidewise from a position laterally of the stand, as indicated atB, below arms 47 of the stand to its operating position A.

With the press in its operating position A, magnet 91 actuates magneticswitch 89 thereby permitting operation of the press when both pushbuttons PB3 and PB4 are depressed. The press is mounted for universalmovement on boom 69 so that as hydraulic cylinder 81 is actuated, upperplaten 11 is moved downwardly to contact the upper side of the uppernailing plate UN. Continued actuation of the hydraulic cylinder causespress frame 79 and lower platen 13 to move upwardly without exerting anysubstantial net upward or downward force on the wood members, which inturncauses the lower platen to engage the lower surface of holder 55 todrive it upwardly until the teeth of the lower nailing plate LN restingthereon contact the lower surface of the wood members. Further actuationof the hydraulic cylinder causes the platens to move toward one anotherdriving the nailing plates into the wood members from above and below.The universal movement of the press permits the lower platen and theupper platen to be simultaneously in position to drive their respectivenailing plates into the wood members without placing any substantial netupward or downward forces on the wood members, and to drive the nailingplates into the wood members with equalized forces on each nailingplate. This equalized application of forces on the wood members preventsany substantial net upward or downward force from being applied to thecantilever arm 47 which would cause the cantilever arms to bend and thewood members to move relative to one another thereby preventing propersecuring by the nailing plates, and enables the efficient production oftrusses having tight, strong joints.

The press 9 is then opened by moving the upper platen 11 away from thelower platen 13 by releasing push buttons PB3 and PB4 and thus reverselyactuating the hydraulic cyliner 81. The holder 55 is gravitybiased toreturn to its lower retracted position as the lower platen movesdownwardly relative to the wood members. By swinging the boom 69'aboutthe pivotal hanger 73 and/or by moving the carriage 75 along the I-beamtrack 77, the press is moved sidewise out of the stand from itsoperating position A through a position such as indicated at C belowarms 47 and then moved completely clear of the stand and along the lineof stands adjacent the wood members M to the next successive stand toassume its operating position therein.

The press is then again operated to drive the respective nailing platesinto the wood members. Due to the cantilever arms 47 permitting lateralor sidewise entry of the lower platen of the press into each stand, thepress may be moved directly from stand-to-stand in one continuousmovement without any significant in and out movement relative to thewood structure (i.e., it is maintained closely adjacent the woodmembers) as it is moved into and out of its sequence of operatingpositions at successive stands.

In contrast, movement of the press of typical prior art apparatus in thesame general field as the apparatus of the present invention, forexample, such prior art apparatus as is shown in my above mentioned U.S.Pat. No. 3,068,484, is illustrated in FIG. 11 (the reference charactersin FIG. 11 corresponding to the reference characters in myabove-mentioned patent). This prior art apparatus included stands 17, 19(as illustrated in FIGS. 3, 4, 7 and 8 in the above-mentioned patent)having two guides 67, 69 at the sides of the stand and a bar 71 at therear thereof for supporting wood members T on the stand (these guidesand bar corresponding to arms 47 and bar 49 of the present invention).Guides 67 and 69 are supported by stand side walls 41 and 43,respectively, so that the lower platen of press 35 may enter the standonly from the front thereof. More particularly, movement of the lowerplaten of press 35 of such prior art apparatus into its operatingposition, as indicated at D in FIG. 11, at successive stands orpedestals 17 or 19 required that the press be moved sidewise (as shownby the arrows in FIG. 11 herein) from a position E at the side and infront of the stand to an entry/exit position F directly in front of thestand. The operator then moved the press inwardly toward its operatingposition D in the stand until the platens were properly positioned atthe stand above and below the wood members supported by the stand. Afteroperation of the press to drive the nailing plates into the woodmembers, the operator backed the press out of its working position toits entry/exit position, and then moved the press sidewise asillustrated at G toward the next successive stand. Thus, it can be seenthat in accordance with the present invention the direct sidewisemovement of the press into and out of its operating position A (see FIG.10) at the various stands requires fewer movements of the press by theoperator than the in-and-out movement of the press required by the priorart apparatus (FIG. 11). Accordingly, this direct movement of the pressfacilitates fabrication of the wood structure and enables more rapid andeconomical production of wood structures. Moreover, the proximitysensing means further markedly improves the, production effectiveness ofthis truss fabricating apparatus in that it functions-to insure rapidand reliable positioning of the press at each stand.

In view of the above, it will be seen that the several objects of theinvention are achieved and other advantageous results attained.

As various changes could be made in the above constructions and methodswithout departing from the scope of the invention, it isintended thatall matter contained in the above description or shown in theaccompanying drawings shall be interpreted as illustrated and not in alimiting sense.

What is claimed is:

1. The method of fabricating wood structures utilizing a C-shaped pressand having an upper platen and a lower platen which are relativelymovable toward and away from one another for driving nailing plates intotwo or more wood members from above and below comprising:

supporting wood members, which are to be nailed together at joints toform a wood structure, on a plurality of stands arranged at said joints,with clearance below the wood members for movement of the lower platenofthe press underneath said wood members;

bringing the press into an operating position at one of said stands withits lower platen below the wood members;

operating the press to drive nailing plates into the wood memberswithout applying any substantial net upward or downward force theretoand then opening the press;

moving the press generally laterally with respect to the presssubstantially sidewise out of said one stand and over to the nextsuccessive stand, maintaining it adjacent the wood member supported bythese stands as it is moved and entering it substantially sidewise intosaid next successive stand to bring it into its operating position atsaid next successive stand for driving nailing plates into the woodmembers;

again operating the press to drive nailing plates into the wood membersand then opening the press; and

repeating the latter two steps as the press is moved bounding thestructure to be fabricated, and the aforesaid steps are carried outalong each of said lines around the structure. b

3. The methodof claim 1 wherein operation of said press is preventedunless said press is at ,an operating position at one of said stands.

4. Apparatus for fabricating wood structures comprising a series ofstands for holding wood members which are to be secured together atjoints by nailing plates to form a wood structure, said stands beingarranged at said joints, each such stand having a support and meanscantilevered relative to the support for holding wood members withclearance therebelow, a C- shaped press having an upper platen and alower platen which are relatively movable toward and away from I oneanother for driving nailing plates into the wood members from above and.below, said press being mounted to permit vertical movement duringdriving the nailing plates into the wood members, and means mountingsaid press for movement of the press into an operating position at oneof said stands for driving nailing plates into the wood members held bysaid one stand, for movement in a generally lateral direction withrespect to the press substantially sidewise out of itsoperating'position at said one stand, and over to the next successivestand, and into its operating position at said next successive standwith said press being maintained substantially adjacent the wood memberssupported by these stands as it is moved, and for driving said nailingplates into the wood members from above and below without exerting anysubstantial net upward or downward force on the wood members by theplatens, the said clearance below the holding means being sufficient forlateral passage of the lower platen of the press below the holdingmeans.

5. Apparatus as set forth in claim 4 wherein said stands supporting thewood members are arranged on lines bounding the wood structure to befabricated.

6. Apparatus asset forth in claim 4 wherein said holding means includesa holder cantilevered outwardly from said support for holding a lowernailing plate to be driven into the wood members from below, saidcantilevered holder being carried by the support for upward and downwardmovement relative to the support.

7. Apparatus as set forth in claim 4 wherein said holding meanscomprises two cantilever arms in sideby-side spaced relation adapted tosupport wood members in position for being secured together by thenailing plates at a location between the arms, said support beingadapted for lateral entry of the lower platen of the press from one sideor the other thereof below said cantilever arms to its operatingposition between said arms with the plane of the top surface of saidarms spaced from the top surface of the lower platen a distancesufficient to accommodate a nailing plate arranged with its teethpointing upwardly for being driven into the wood members from below, thecantilever arms being laterally spaced from one another a distancegreater than the width of the lower platen of the press for entry of thelower platen of the press between the arms when the lower platen ismoved upwardly to drive a nailing plate upwardly into the wood members.

8. Apparatus as set forth in claim 7 wherein said holding means furtherincludes a holder for holding a lower nailing plate to be driven intothe wood members from below, said holder being .carried by the supportfor upward movement between said arms by the lower platen of the pressfrom a lowered retracted position below the plane of the top surface ofsaid arms to drive a nailing plate positioned thereon into the woodmembers from below.

9. Apparatus as set forth in claim 8 wherein said support includes abase, said arms being cantilevered forward over the base and spacedabove the base for the lateral entry of the lower platen of the pressfrom one side or the other of the stand between the base and the arms.

10. Apparatus as set forth in claim 9 having means for supporting saidholder movable upwardly and downwardly at one side of the baseconstituting the back of the base, said holder being a platecantilevered forward over the base, the lowered retracted position ofthe holder plate being generally below the level of the top surface ofsaid arms a distance sufficient to accommodate a nailing plate with itsteeth pointing upwardly for being driven into the wood members frombelow and being spaced above the base a distance sufficient for entry ofthe lower platen of the press.

11. Apparatus as set forth in claim 10 wherein said holder platesupporting means comprises a pair of vertical rods secured to saidholder plate with the latter extending forwardly from the upper ends ofsaid rods, and guide means carried by the stand for guiding said holderplate during movement between its lowered retracted position and araised operative position in which a nailing plate held thereby isdriven into wood members from below.

12. Apparatus as set forth in claim 11 wherein said base has a top andsaid support includes supporting means for said arms extending upwardlyabove the top of the base at the back thereof.

13. Apparatus as set forth in claim 12 wherein said supporting means forsaid arms comprises a hollow wall extending upwardly from the base atthe back thereof, said arms extending forwardly over the base from thesides of said wall at the top thereof and being located above the top ofsaid wall, said apparatus further having a bar at the level of said armsextending between the back ends of said arms, said rods being movable upand down in said wall and the holder plate extending forwardly therefromover the top of said wall.

14. Apparatus as set forth in claim 11 wherein said guide meanscomprises a pair of grooved rollers carried by said support for each ofsaid rods, said rollers of each pair being disposed on opposite sides oftheir respective rod for guiding the rod as said holder plate is movedbetween its lowered retracted position and said raised position fordriving said nailing plate into the wood members from below.

15. Apparatus as set forth in claim 11 wherein said guide meanscomprises a pair of rollers carried by each of said rods, said rollersbeing engageable with a portion of said support for guiding the rod assaid holder plate is moved between its lowered retracted position andsaid raised positionfor driving said nailing plate into the wood membersfrom below.

16. Apparatus as set forth in claim 4 further comprising means forpreventing operation of the press unless the press is at an operatingposition at one of said stands. 1

17. Apparatus as set forth in claim 16 wherein the last-said meansincludes proximity sensing means responsivev to movement of the pressinto its operating position at each of said stands.

18. Apparatus as set forth in claim 17 wherein said proximity sensingmeans comprises a proximity switch actuable in response to a magneticfield of a predetermined strength, and means for producing a magneticfield of sufficient strength to actuate said proximity switch when saidpress is at its operating position at one of said stands thereby topermit operation of the press,

19. Apparatus as set forth in claim 18 wherein said proximity switch iscarried by said press and said field producing means is a magnet carriedby each of said stands so that with the press positioned at itsoperating position at a stand, said proximity switch being actuated bythe field of the magnet carried by the stand.

20. Apparatus as setforth in claim 19 which further includes a circuitfor initiating movement of said press platens toward one another fordriving nailing plates into the wood members, said proximity switchbeing connected in said circuit whereby said press may be operated onlywhen the press is at its operating position at one of said stands andsaid proximity switch is actuated to energize said circuit.

21. Apparatus as set forth in claim 20 wherein said circuit includes atleast one manually operable switch, said proximity switch being seriallyconnected in said circuit with said manually operable switch wherebysaid press may be operated only when the press is at its operatingposition at one of said stands and both of said switches are actuated.

22. Apparatus for fabricating wood structures comprising a series ofstands for holding wood members which are to be secured together atjoints by nailing plates to form a wood structure, said stands beingarranged at said joints, a press having an upper platen and a lowerplaten which are relatively movable toward and away from one another fordriving nailing plates into the wood members from above and below, meansmounting said press for generally lateral movement of the presssubstantially sidewise into and away from an operating position at eachof said stands, and means for preventing operation of the press unlessthe press is at an operating position at one of said stands.

23. Apparatus as set forth in claim 22 wherein each such stand includesa support and holding means cantilevered relative to the support forholding wood members with clearance therebelow.

24. Apparatus as set forth in claim 23 wherein said holding meansincludes a holder cantilevered outwardly from said support for holding alower nailing plate to be driven into the wood members from below, saidcantilevered holder being carried by the support for upward and downwardmovement relative to the support.

25. Apparatus as set forth in claim 22 wherein the last said meansincludes proximity sensing means responsive to the movement of the pressinto an operating position at each of the stands.

26. Apparatus as set forth in claim 25 wherein said proximity sensingmeans comprises a proximity switch actuable in response to a magneticfield of a predetermined strength, and means for producing a magneticfield of sufficient strength to actuate said proximity switch when saidpress is at its operating position at one of said stands thereby topermit operation of the press.

27. Apparatus as set forth in claim 26 wherein said proximity switch iscarried by said press and said field producing means is a magnet carriedby each of said stands so that with the press positioned at itsoperating position at a stand, said proximity switch is actuated by thefield of said magnet carried by the stand.

28. Apparatus as set forth in claim 2 which further includes a circuitfor initiating movement of said press platens toward one another fordriving nailing plates into the wood members, said proximity switchbeing connected in said circuit whereby said press may be operated onlywhen the press is at its operating position at one of said stands andsaid proximity switch is actuated to energize said circuit.

29. Apparatus as set forth in claim 28 wherein said circuit includes atleast one manually operable switch, said proximity switch being seriallyconnected in said circuit with said manually operable switch wherebysaid press may be operated only when the press is at its operatingposition at one of said stands and both of said switches are actuated.

P UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. i rDated July 23 1274 Invenmflg) Walter G.. Moehlenpah It is certified thaterror appears in the above-identified patent and that said Lette tsPatent are hereby corrected as shown below:

!" Column 1, 'line'45, "light" should read --tight--. Column 8 line 9,"liquid" vshould read -fluid--. Column 14, claim 28, line 1, "claim '2"should read --claim 27--.

Signed and sealed this 29th day of October 1974.

(SEAL) Attest:

McCOY M. CIBsON JR. c. MARSHALL DANN Atte'sting Offlce r Commissioner ofPatents

1. The method of fabricating wood structures utilizing a Cshaped pressand having an upper platen and a lower platen which are relativelymovable toward and away from one another for driving nailing plates intotwo or more wood members from above and below comprising: supportingwood members, which are to be nailed together at joints to form a woodstructure, on a plurality of stands arranged at said joints, withclearance below the wood members for movement of the lower platen of thepress underneath said wood members; bringing the press into an operatingposition at one of said stands with its lower platen below the woodmembers; operating the press to drive nailing plates into the woodmembers without applying any substantial net upward or downward forcethereto and then opening the press; moving the press generally laterallywith respect to the press substantially sidewise out of said one standand over to the next successive stand, maintaining it adjacent the woodmember supported by these stands as it is moved and entering itsubstantially sidewise into said next successive stand to bring it intoits operating position at said next successive stand for driving nailingplates into the wood members; again operating the press to drive nailingplates into the wood members and then opening the press; and repeatingthe latter two steps as the press is moved between successive standsthereby to nail additional wood joints.
 2. The method of claim 1 whereinwood members are supported on a plurality of stands arranged on linesbounding the structure to be fabricated, and the aforesaid steps arecarried out along each of said lines around the structure.
 3. The methodof claim 1 wherein operation of said press is prevented unless saidpress is at an operating position at one of said stands.
 4. Apparatusfor fabricating wood structures comprising a series of stands forholding wood members which are to be secured together at joints bynailing plates to form a wood structure, said stands being arranged atsaid joints, each such stand having a support and means cantileveredrelative to the support for holding wood members with clearancetherebelow, a C-shaped press having an upper platen and a lower platenwhich are relatively movable toward and away from one another fordriving nailing plates into the wood members from above and below, saidpress being mounted to permit vertical movement during driving thenailing plates into the wood members, and means mounting said press formovement of the press into an operating position at one of said standsfor driving nailing plates into the wood members held by said one stand,for movement in a generally lateral direction with respect to the presssubstantially sidewise out of its operating position at said one stand,and over to the next successive stand, and into its operating positionat said next successive stand with said press being maintainedsubstantially adjacent the wood members supported by these stands as itis moved, and for driving said nailing plates into the wood members fromabove and below without exerting any substantial net upward or downwardforce on the wood members by the platens, the said clearance below theholding means being sufficient for lateral passage of the lower platenof the press below the holding means.
 5. Apparatus as set forth in claim4 wherein said stands supporting the wood members are arranged on linesbounding the wood structure to be fabricated.
 6. Apparatus as set forthin claim 4 wherein said holding means includes a holder cantileveredoutwardly from said support for holding a lower nailing plate to bedriven into the wood members from below, said cantilevered holder beingcarried by the support foR upward and downward movement relative to thesupport.
 7. Apparatus as set forth in claim 4 wherein said holding meanscomprises two cantilever arms in side-by-side spaced relation adapted tosupport wood members in position for being secured together by thenailing plates at a location between the arms, said support beingadapted for lateral entry of the lower platen of the press from one sideor the other thereof below said cantilever arms to its operatingposition between said arms with the plane of the top surface of saidarms spaced from the top surface of the lower platen a distancesufficient to accommodate a nailing plate arranged with its teethpointing upwardly for being driven into the wood members from below, thecantilever arms being laterally spaced from one another a distancegreater than the width of the lower platen of the press for entry of thelower platen of the press between the arms when the lower platen ismoved upwardly to drive a nailing plate upwardly into the wood members.8. Apparatus as set forth in claim 7 wherein said holding means furtherincludes a holder for holding a lower nailing plate to be driven intothe wood members from below, said holder being carried by the supportfor upward movement between said arms by the lower platen of the pressfrom a lowered retracted position below the plane of the top surface ofsaid arms to drive a nailing plate positioned thereon into the woodmembers from below.
 9. Apparatus as set forth in claim 8 wherein saidsupport includes a base, said arms being cantilevered forward over thebase and spaced above the base for the lateral entry of the lower platenof the press from one side or the other of the stand between the baseand the arms.
 10. Apparatus as set forth in claim 9 having means forsupporting said holder movable upwardly and downwardly at one side ofthe base constituting the back of the base, said holder being a platecantilevered forward over the base, the lowered retracted position ofthe holder plate being generally below the level of the top surface ofsaid arms a distance sufficient to accommodate a nailing plate with itsteeth pointing upwardly for being driven into the wood members frombelow and being spaced above the base a distance sufficient for entry ofthe lower platen of the press.
 11. Apparatus as set forth in claim 10wherein said holder plate supporting means comprises a pair of verticalrods secured to said holder plate with the latter extending forwardlyfrom the upper ends of said rods, and guide means carried by the standfor guiding said holder plate during movement between its loweredretracted position and a raised operative position in which a nailingplate held thereby is driven into wood members from below.
 12. Apparatusas set forth in claim 11 wherein said base has a top and said supportincludes supporting means for said arms extending upwardly above the topof the base at the back thereof.
 13. Apparatus as set forth in claim 12wherein said supporting means for said arms comprises a hollow wallextending upwardly from the base at the back thereof, said armsextending forwardly over the base from the sides of said wall at the topthereof and being located above the top of said wall, said apparatusfurther having a bar at the level of said arms extending between theback ends of said arms, said rods being movable up and down in said walland the holder plate extending forwardly therefrom over the top of saidwall.
 14. Apparatus as set forth in claim 11 wherein said guide meanscomprises a pair of grooved rollers carried by said support for each ofsaid rods, said rollers of each pair being disposed on opposite sides oftheir respective rod for guiding the rod as said holder plate is movedbetween its lowered retracted position and said raised position fordriving said nailing plate into the wood members from below. 15.Apparatus as set forth in claim 11 wherein said guide means comprises apair of rollers carried by each of said rods, said rollers beingengageable with a portion of said support for guiding the rod as saidholder plate is moved between its lowered retracted position and saidraised position for driving said nailing plate into the wood membersfrom below.
 16. Apparatus as set forth in claim 4 further comprisingmeans for preventing operation of the press unless the press is at anoperating position at one of said stands.
 17. Apparatus as set forth inclaim 16 wherein the last-said means includes proximity sensing meansresponsive to movement of the press into its operating position at eachof said stands.
 18. Apparatus as set forth in claim 17 wherein saidproximity sensing means comprises a proximity switch actuable inresponse to a magnetic field of a predetermined strength, and means forproducing a magnetic field of sufficient strength to actuate saidproximity switch when said press is at its operating position at one ofsaid stands thereby to permit operation of the press.
 19. Apparatus asset forth in claim 18 wherein said proximity switch is carried by saidpress and said field producing means is a magnet carried by each of saidstands so that with the press positioned at its operating position at astand, said proximity switch being actuated by the field of the magnetcarried by the stand.
 20. Apparatus as set forth in claim 19 whichfurther includes a circuit for initiating movement of said press platenstoward one another for driving nailing plates into the wood members,said proximity switch being connected in said circuit whereby said pressmay be operated only when the press is at its operating position at oneof said stands and said proximity switch is actuated to energize saidcircuit.
 21. Apparatus as set forth in claim 20 wherein said circuitincludes at least one manually operable switch, said proximity switchbeing serially connected in said circuit with said manually operableswitch whereby said press may be operated only when the press is at itsoperating position at one of said stands and both of said switches areactuated.
 22. Apparatus for fabricating wood structures comprising aseries of stands for holding wood members which are to be securedtogether at joints by nailing plates to form a wood structure, saidstands being arranged at said joints, a press having an upper platen anda lower platen which are relatively movable toward and away from oneanother for driving nailing plates into the wood members from above andbelow, means mounting said press for generally lateral movement of thepress substantially sidewise into and away from an operating position ateach of said stands, and means for preventing operation of the pressunless the press is at an operating position at one of said stands. 23.Apparatus as set forth in claim 22 wherein each such stand includes asupport and holding means cantilevered relative to the support forholding wood members with clearance therebelow.
 24. Apparatus as setforth in claim 23 wherein said holding means includes a holdercantilevered outwardly from said support for holding a lower nailingplate to be driven into the wood members from below, said cantileveredholder being carried by the support for upward and downward movementrelative to the support.
 25. Apparatus as set forth in claim 22 whereinthe last said means includes proximity sensing means responsive to themovement of the press into an operating position at each of the stands.26. Apparatus as set forth in claim 25 wherein said proximity sensingmeans comprises a proximity switch actuable in response to a magneticfield of a predetermined strength, and means for producing a magneticfield of sufficient strength to actuate said proximity switch when saidpress is at its operating position at one of said stands thereby topermit operation of the press.
 27. Apparatus as set forth in claim 26wherein said proximity switch is carried by said press and said fieldproducing means is a magnet carried by each of said stands so that withthe press positioned at its operating position at a stand, saidproximity switch is actuated by the field of said magnet carried by thestand.
 28. Apparatus as set forth in claim 2 which further includes acircuit for initiating movement of said press platens toward one anotherfor driving nailing plates into the wood members, said proximity switchbeing connected in said circuit whereby said press may be operated onlywhen the press is at its operating position at one of said stands andsaid proximity switch is actuated to energize said circuit. 29.Apparatus as set forth in claim 28 wherein said circuit includes atleast one manually operable switch, said proximity switch being seriallyconnected in said circuit with said manually operable switch wherebysaid press may be operated only when the press is at its operatingposition at one of said stands and both of said switches are actuated.